<?php
/**
 * This code is licensed under the BSD 3-Clause License.
 *
 * Copyright (c) 2017, Maks Rafalko
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * * Neither the name of the copyright holder nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

declare(strict_types=1);

namespace Infection\Benchmark;

use Closure;
use LogicException;
use function sprintf;
use Symfony\Component\Console\Style\SymfonyStyle;

final class DummyInstrumentor implements Instrumentor
{
    public function profile(Closure $createMain, int $sampleSize, SymfonyStyle $io): int
    {
        $result = null;

        for ($i = 0; $i < $sampleSize; ++$i) {
            $main = $createMain();

            $previousResult = $result;
            $result = $main();

            self::ensureResultInvariance($previousResult, $result);
        }

        return $result;
    }

    private static function ensureResultInvariance(
        ?int $previous,
        int $new,
    ): void {
        if ($previous !== null && $new !== $previous) {
            throw new LogicException(
                sprintf(
                    'Expected the script to return the same output for each sample. Expected %d but got %d.',
                    $previous,
                    $new,
                ),
            );
        }
    }
}
